Erect a monument instead of a single grave: if a man never leaves his mother-in-law, his father must have his mother, which means that one of the husband and wife is dead and the other is still alive. Some of them have been erected, so it is best not to engrave the party's name or paint it with red paint.
Don't erect a monument three years ago: generally speaking, according to the calculation of people who died later, a monument will be erected three years later. Some people set up a monument to their ancestors on the third anniversary. Also have a plenty of ancestors after three years, Tomb-Sweeping Day or the Mid-Autumn Festival on October 1st of the lunar calendar.